If a valve doesn’t operate, your course of doesn’t run, and that’s money down the drain. Or worse, a spurious journey shuts the method down. Or worst of all, a valve malfunction leads to a dangerous failure. Solenoid valves in oil and gas purposes control the actuators that move massive process valves, including in emergency shutdown (ESD) methods. The solenoid must exhaust air to enable the ESD valve to return to fail-safe mode every time sensors detect a harmful process situation. These valves must be quick-acting, sturdy and, above all, reliable to forestall downtime and the associated losses that happen when a process isn’t working.
And this is much more necessary for oil and fuel operations the place there might be limited power out there, such as distant wellheads or satellite tv for pc offshore platforms. Here, solenoids face a double reliability challenge. First, a failure to function appropriately cannot only trigger pricey downtime, however a maintenance call to a remote location additionally takes longer and costs greater than a neighborhood repair. Second, to scale back the demand for energy, many valve producers resort to compromises that truly cut back reliability. This is dangerous sufficient for process valves, however for emergency shutoff valves and different safety instrumented methods (SIS), it is unacceptable.
Poppet valves are generally higher suited than spool valves for distant areas as a outcome of they are much less complicated. For low-power applications, look for a solenoid valve with an FFR of 10 and a design that isolates the media from the coil. (Courtesy of Norgren Inc.)
Choosing a reliable low-power solenoid
Many components can hinder the reliability and efficiency of a solenoid valve. Friction, media move, sticking of the spool, magnetic forces, remanence of electrical present and material traits are all forces solenoid valve manufacturers have to overcome to build probably the most dependable valve.
High spring pressure is key to offsetting these forces and the friction they cause. However, in low-power applications, most producers have to compromise spring force to permit the valve to shift with minimal energy. The reduction in spring force ends in a force-to-friction ratio (FFR) as little as 6, although the commonly accepted security stage is an FFR of 10.
Several components of valve design play into the quantity of friction generated. Optimizing each of those allows a valve to have larger spring force while nonetheless sustaining a excessive FFR.
For example, the valve operates by electromagnetism — a present stimulates the valve to open, allowing the media to flow to the actuator and transfer the process valve. This media could also be air, but it could also be natural gasoline, instrument fuel and even liquid. This is very true in remote operations that must use no matter media is available. This means there’s a trade-off between magnetism and corrosion. Valves in which the media is out there in contact with the coil must be made from anticorrosive materials, which have poor magnetic properties. A valve design that isolates the media from the coil — a dry armature — allows using extremely magnetized materials. As a end result, there isn’t any residual magnetism after the coil is de-energized, which in flip permits quicker response occasions. This design additionally protects reliability by stopping contaminants within the media from reaching the inside workings of the valve.
Another issue is the valve housing design. Usually a heavy (high-force) spring requires a high-power coil to beat the spring strength. Integrating the valve and coil right into a single housing improves effectivity by preventing vitality loss, allowing for using a low-power coil, resulting in much less power consumption with out diminishing FFR. This built-in coil and housing design also reduces warmth, stopping spurious journeys or coil burnouts. A dense, thermally environment friendly (low-heat generating) coil in a housing that acts as a heat sink, designed with no air hole to lure warmth across the coil, nearly eliminates coil burnout considerations and protects course of availability and security.
Poppet valves are usually better suited than spool valves for remote operations. The decreased complexity of poppet valves will increase reliability by reducing sticking or friction factors, and reduces the variety of components that can fail. Spool valves often have large dynamic seals and plenty of require lubricating grease. Over time, particularly if the valves aren’t cycled, the seals stick and the grease hardens, resulting in higher friction that should be overcome. There have been stories of valve failure due to moisture in the instrument media, which thickens the grease.
A direct-acting valve is your best option wherever possible in low-power environments. Not only is the design much less complicated than an indirect-acting piloted valve, but also pilot mechanisms usually have vent ports that can admit moisture and contamination, resulting in corrosion and permitting the valve to stick in the open position even when de-energized. Also, direct-acting solenoids are particularly designed to shift the valves with zero minimum pressure necessities.
Note that some larger actuators require excessive move charges and so a pilot operation is critical. In this case, it is important to ascertain that all components are rated to the identical reliability score as the solenoid.
Finally, since most remote locations are by definition harsh environments, a solenoid installed there will must have strong development and have the power to stand up to and function at extreme temperatures while still sustaining the identical reliability and safety capabilities required in less harsh environments.
When deciding on a solenoid management valve for a remote operation, it’s possible to discover a valve that doesn’t compromise performance and reliability to minimize back power demands. Look for a excessive FFR, easy dry armature design, nice magnetic and warmth conductivity properties and strong construction.
เกจวัดแรงดันไนโตรเจนราคา is the sales engineer for the Energy Sector of IMI Precision Engineering, makers of IMI Norgren, IMI Maxseal and IMI Herion brand parts for power operations. He provides cross-functional experience in software engineering and enterprise development to the oil, gasoline, petrochemical and power industries and is certified as a pneumatic Specialist by the International Fluid Power Society (IFPS).
Collin Skufca is the key account supervisor for the Energy Sector for IMI Precision Engineering. He provides experience in new business development and buyer relationship administration to the oil, fuel, petrochemical and power industries and is licensed as a pneumatic specialist by the International Fluid Power Society (IFPS).
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